The distal radioulnar articulation or inferior radioulnar joint is a joint formed between the head of the ulna and the ulnar notch on the distal radius.
The articular surfaces are connected together by the following ligaments:
- Volar radioulnar ligament
- Dorsal radioulnar ligament
- Articular disk (Triangular fibrocartilage)
Triangular fibrocartilage complex is ulnar continuation of distal radius & presents concave surface for articulation with lunate and triquetrium.
Distal radio ulnar joint is involved in pronation and supination movements of the forearm. In pronation, ulna assumes a small relative negative variance position, ulnar head moves dorsally, and volar ligaments become tight;
In supination, ulna assumes a small relative positive variance position, ulnar head moves volarly, and dorsal ligaments become tight.